From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932911AbdC2SSc (ORCPT ); Wed, 29 Mar 2017 14:18:32 -0400 Received: from mail-pg0-f54.google.com ([74.125.83.54]:35715 "EHLO mail-pg0-f54.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932401AbdC2SQ0 (ORCPT ); Wed, 29 Mar 2017 14:16:26 -0400 From: Kees Cook To: kernel-hardening@lists.openwall.com Cc: Kees Cook , Mark Rutland , Andy Lutomirski , Hoeun Ryu , PaX Team , Emese Revfy , Russell King , x86@kernel.org, linux-kernel@vger.kernel.org, linux-arm-kernel@lists.infradead.org Subject: [RFC v2][PATCH 07/11] ARM: mm: set DOMAIN_WR_RARE for rodata Date: Wed, 29 Mar 2017 11:15:59 -0700 Message-Id: <1490811363-93944-8-git-send-email-keescook@chromium.org> X-Mailer: git-send-email 2.7.4 In-Reply-To: <1490811363-93944-1-git-send-email-keescook@chromium.org> References: <1490811363-93944-1-git-send-email-keescook@chromium.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org This creates DOMAIN_WR_RARE for the kernel's .rodata section, separate from DOMAIN_KERNEL to avoid predictive fetching in device memory during a DOMAIN_MANAGER transition. TODO: handle kernel module vmalloc memory, which needs to be marked as DOMAIN_WR_RARE too, for module .rodata sections. Signed-off-by: Kees Cook --- arch/arm/include/asm/domain.h | 3 +++ arch/arm/mm/dump.c | 2 ++ arch/arm/mm/init.c | 7 ++++--- 3 files changed, 9 insertions(+), 3 deletions(-) diff --git a/arch/arm/include/asm/domain.h b/arch/arm/include/asm/domain.h index 8b33bd7f6bf9..b5ca80ac823c 100644 --- a/arch/arm/include/asm/domain.h +++ b/arch/arm/include/asm/domain.h @@ -43,6 +43,7 @@ #define DOMAIN_IO 0 #endif #define DOMAIN_VECTORS 3 +#define DOMAIN_WR_RARE 4 /* * Domain types @@ -69,11 +70,13 @@ #define DACR_INIT \ (__DACR_INIT_USER | \ domain_val(DOMAIN_KERNEL, DOMAIN_MANAGER) | \ + domain_val(DOMAIN_WR_RARE, DOMAIN_CLIENT) | \ domain_val(DOMAIN_IO, DOMAIN_CLIENT) | \ domain_val(DOMAIN_VECTORS, DOMAIN_CLIENT)) #define __DACR_DEFAULT \ domain_val(DOMAIN_KERNEL, DOMAIN_CLIENT) | \ + domain_val(DOMAIN_WR_RARE, DOMAIN_CLIENT) | \ domain_val(DOMAIN_IO, DOMAIN_CLIENT) | \ domain_val(DOMAIN_VECTORS, DOMAIN_CLIENT) diff --git a/arch/arm/mm/dump.c b/arch/arm/mm/dump.c index 35ff45470dbf..b1aa9a17e0c3 100644 --- a/arch/arm/mm/dump.c +++ b/arch/arm/mm/dump.c @@ -288,6 +288,8 @@ static const char *get_domain_name(pmd_t *pmd) return "IO "; case PMD_DOMAIN(DOMAIN_VECTORS): return "VECTORS"; + case PMD_DOMAIN(DOMAIN_WR_RARE): + return "WR_RARE"; default: return "unknown"; } diff --git a/arch/arm/mm/init.c b/arch/arm/mm/init.c index 1d8558ff9827..d54a74b5718b 100644 --- a/arch/arm/mm/init.c +++ b/arch/arm/mm/init.c @@ -642,9 +642,10 @@ static struct section_perm ro_perms[] = { .mask = ~L_PMD_SECT_RDONLY, .prot = L_PMD_SECT_RDONLY, #else - .mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE), - .prot = PMD_SECT_APX | PMD_SECT_AP_WRITE, - .clear = PMD_SECT_AP_WRITE, + .mask = ~(PMD_SECT_APX | PMD_SECT_AP_WRITE | PMD_DOMAIN_MASK), + .prot = PMD_SECT_APX | PMD_SECT_AP_WRITE | \ + PMD_DOMAIN(DOMAIN_WR_RARE), + .clear = PMD_SECT_AP_WRITE | PMD_DOMAIN(DOMAIN_KERNEL), #endif }, }; -- 2.7.4